000
FXUS66 KEKA 031157
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
357 AM PST TUE MAR 3 2015
.SYNOPSIS...HIGH PRESSURE WILL BUILD OVER NORTHWEST CALIFORNIA
THIS WEEK BRINGING DRY CONDITIONS AND A GRADUAL WARMUP THROUGH
THIS COMING WEEKEND. LOW TEMPERATURES FOR THE NEXT COUPLE OF
NIGHTS WILL FALL INTO THE 30S IN SEVERAL AREAS ALLOWING FOR SOME
FROST TO DEVELOP.
&&
.DISCUSSION...LINGERING LOW LEVEL MOISTURE BEHIND A DEPARTING LOW
PRESSURE SYSTEM HAS KEPT DEWPOINTS ELEVATED RESTRICTING RADIATIONAL
COOLING THIS MORNING. TEMPERATURES ARE JUST NOW REACHING THE UPPER
TO MIDDLE 30S IN INTERIOR MENDOCINO COUNTY AND A FEW ISOLATED
LOCATIONS OF COASTAL HUMBOLDT AND COASTAL MENDOCINO COUNTIES. AT
THIS TIME...WIDESPREAD FROST STILL LOOKS ONLY MOST LIKELY ACROSS
INTERIOR MENDOCINO COUNTY SO HAVE OPTED TO NOT EXPAND THE FROST
ADVISORIES TO THE COAST FOR THIS MORNING. DEWPOINTS SHOULD
CONTINUE TO DECREASE TODAY INTO TONIGHT ALLOWING FOR BETTER
RADIATIONAL COOLING TONIGHT AS HIGH PRESSURE BUILDS OVER NORTHWEST
CALIFORNIA. THUS...FROST ADVISORIES HAVE BEEN ISSUED FOR COASTAL
AREAS AND A FREEZE WATCH HAS BEEN ISSUED FOR INTERIOR MENDOCINO
COUNTY FOR TONIGHT. THE FREEZE WATCH WILL NEED TO BE UPGRADED TO A
WARNING OR FROST ADVISORY LATER THIS MORNING AFTER THE CURRENTLY
RUNNING FROST ADVISORY EXPIRES.
ALL MODEL GUIDANCE INDICATES THAT A RIDGE OF HIGH PRESSURE WILL
CONTINUE TO BUILD OVER THE WEST COAST INTO THIS WEEKEND BRINGING
WARMER TEMPERATURES AND DRY CONDITIONS. AFTERNOON HIGH TEMPERATURES
WILL CLIMB INTO THE 70S IN MENDOCINO COUNTY BY LATE WEEK AND
POSSIBLY REACH INTO THE UPPER 70S OVER THE WEEKEND. ELSEWHERE HIGH
TEMPERATURES WILL REMAIN PRIMARILY IN THE 60S WITH A FEW UPPER 50S
ALONG THE IMMEDIATE COAST.
HIGH RESOLUTION MODEL GUIDANCE INDICATES THAT STRATUS MAY REDEVELOP
OFF THE COAST THURSDAY INTO FRIDAY BRINGING THE POTENTIAL FOR LOW
CLOUDS AND FOG FOR COASTAL AREAS. CLOUD COVER HAS BEEN INCREASED
WITH THIS UPDATE THURSDAY THROUGH FRIDAY MORNING ACROSS COASTAL
LOCATIONS. THERE IS SOME HINT OF LIGHT OFFSHORE FLOW WHICH WILL
LIKELY KEEP THE STRATUS FROM PENETRATING TOO FAR UP COASTAL VALLEYS.
/RPA
&&
.AVIATION...EXPECT MOSTLY VFR TODAY WITH THE EXCEPTION OF SOME LOW
LEVEL CLOUD COVER ACROSS THE EEL RIVER DELTA AND SOME INTERIOR
VALLEYS THIS MORNING. THIS CLOUD COVER SHOULD DIMINISH BY THE LATE
MORNING HOURS, HOWEVER, HIGHER CLOUDS WILL FILTER OVER THE REGION
AHEAD OF AN APPROACHING SHORTWAVE TROUGH THIS AFTERNOON. IN
ADDITION, THIS TROUGH WILL BRING SOME GUSTY WINDS LATE THIS
AFTERNOON INTO THE EARLY EVENING. LOW CLOUD COVER COULD DEVELOP IN
SIMILAR SPOTS AGAIN TONIGHT BUT DRY OFFSHORE FLOW WILL HELP CLEAR IT
OUT LATE IN THE TAF PERIOD. /KML
&&
.MARINE...WINDS HAVE BEGUN TO SLOWLY DIMINISH ACROSS THE COASTAL
WATERS AS THE SURFACE PRESSURE GRADIENT WEAKENS BEHIND THE PASSING
LOW PRESSURE SYSTEM. AS A RESULT, GALES WERE ALLOWED TO EXPIRE EARLY
THIS MORNING. FRESH WINDS WILL LINGER THROUGH THE DAY WITH A QUICK
RAMP UP LATE THIS AFTERNOON INTO THE EVENING AS AN ADDITIONAL
SHORTWAVE TROUGH PASSES OVER THE REGION CAUSING THE GRADIENT TO
CONTRACT. NORTHERLY WINDS WILL CONTINUE TO DECLINE WEDNESDAY AND
REMAIN LIGHT TO MODERATE WITH VARYING DIRECTIONS THROUGH THE WEEKEND
AS A RIDGE OF HIGH PRESSURE THAT IS CURRENTLY OVER THE EASTERN
PACIFIC SHIFTS TOWARDS THE PACIFIC NORTHWEST. THE OVERALL SEA STATE
WILL GRADUALLY SUBSIDE IN RESPONSE TO THE DIMINISHING WINDS.
HAZARDOUS SEAS WARNINGS WERE ISSUED FOR THE OUTER WATERS THROUGH
LATER THIS MORNING TO ACCOUNT FOR THE LINGERING STEEP SEAS WITH
SMALL CRAFT ADVISORIES FOLLOWING THROUGH WEDNESDAY EVENING. AN
ADVISORY MAY BE NEEDED FOR THE NORTHERN INNER WATERS THIS AFTERNOON
WITH THE SPURT OF WINDS HOWEVER SMALL CRAFT WINDS LOOK TO BE
MARGINAL AND SHORT LIVED. WILL ALLOW THE DAY SHIFT TO ASSESS AND
ISSUE IF NECESSARY. SEAS WILL CONTINUE TO SETTLE LATE IN THE WEEK AS
THE SHORTER PERIOD WAVE SYSTEMS DIMINISH LEAVING MID TO LONG PERIOD
WAVES TO DOMINATE THE MARINE ENVIRONMENT INTO THE WEEKEND. /KML
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
FROST ADVISORY FROM 1 AM TO 7 AM PST WEDNESDAY FOR CAZ001-002.
FROST ADVISORY UNTIL 8 AM PST THIS MORNING FOR CAZ076.
FREEZE WATCH FROM LATE TONIGHT THROUGH WEDNESDAY MORNING FOR
CAZ076.
NORTHWEST CALIFORNIA COASTAL WATERS...
SMALL CRAFT ADVISORY UNTIL 9 AM PST THIS MORNING FOR PZZ450-455.
SMALL CRAFT ADVISORY UNTIL 9 PM PST WEDNESDAY FOR PZZ470.
HAZARDOUS SEAS WARNING UNTIL 9 AM PST THIS MORNING FOR
PZZ470-475.
SMALL CRAFT ADVISORY UNTIL 3 PM PST WEDNESDAY FOR PZZ475.
&&
$$
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